ISSN 0300-9092 (Print)
ISSN 2412-5679 (Online)

Immunological markers of successful implantation in assisted reproductive technologies

Kurushin N.D., Amyan T.S., Bychkova N.V., Krechetova L.V., Gavisova A.A.

Academician V.I. Kulakov National Medical Research Centre for Obstetrics, Gynecology and Perinatology, Ministry of Health of Russia, Moscow, Russia

Embryo implantation is a complex biological process involving the interaction between the decidua and the semi‑allogeneic embryo. In a normal pregnancy, the maternal immune system does not reject the semi‑allogenic fetus but instead supports its development. Immunological tolerance is maintained by a complex system of interactions within the decidua between immune, stromal and trophoblast cells. The maternal immune cells are believed to regulate the extent of trophoblast invasion and the remodeling of the spiral arteries, thereby ensuring a normal blood supply to the fetus. Thus, impaired immune regulation may be one of the most important factors contributing to reproductive disorders.
The aim of this review is to analyze current data on the role of cellular and molecular components of the immune system in formation of the implantation window and their involvement in the pathogenesis of reproductive disorders, as well as to assess the diagnostic value of immunological biomarkers of endometrial receptivity and their potential use in clinical practice.
The article summarises data on the functions and roles of key immune cells in the endometrium, including NK cells, regulatory T cells, dendritic cells and macrophages, and examines the significance of immunoregulatory molecules in creating a favourable immune environment at the level of maternal-embryonic interaction.
Conclusion. The data presented suggest that the immunological microenvironment of the endometrium plays an important role in successful implantation. Integrating immunological markers of receptivity into clinical practice may improve diagnosis and facilitate the development of personalized treatment approaches for patients experiencing repeated failures of assisted reproductive technology programs. 

Authors’ contributions. Kurushin N.D., Amyan T.S. – the search and analysis of literature, writing the text of the article; Bychkova N.V., Krechetova L.V., Gavisova А.А. – editing and final approval of the article.
Conflicts of interest. Authors declare lack of the possible conflicts of interests.
Funding. The work was carried out without financial support.  
Generative Artificial Intelligence. No generative artificial intelligence technologies were used in the preparation of this article.
For citation: Kurushin N.D., Amyan T.S., Bychkova N.V., Krechetova L.V., Gavisova A.A. 
Immunological markers of successful implantation in assisted reproductive technologies. 
Akusherstvo i Ginekologiya/Obstetrics and Gynecology. 2026; (10): 20-27 (in Russian)
https://dx.doi.org/10.18565/aig.2026.158

Keywords

recurrent implantation failure
endometrial receptivity
immunological biomarkers
reproductive medicine

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Received 06.05.2026

Accepted 02.09.2026

About the Authors

Nikita D. Kurushin, PhD student, 1st Gynecological Departament of the Institute of Reproductive Medicine, Academician V.I. Kulakov National Medical Research
Center for Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, 117997, Russia, Moscow, Ac. Oparin str., 4, +7(926)159-13-03, kurushinniko@gmail.com,
https://orcid.org/0009-0009-9956-1724
Tatiana S. Amyan, PhD, gynaecologist, 1st Gynecological Departament of the Institute of Reproductive Medicine, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, 117997, Russia, Moscow, Ac. Oparin str., 4, +7(926)163-28-33, t_amyan@oparina4.ru,
https://orcid.org/0009-0004-3772-2346
Nataliya V. Bychkova, Dr. Bio. Sci, Senior Researcher at the Laboratory of Clinical Immunology of the Institute of Reproductive Medicine, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, 117997, Russia, Moscow, Ac. Oparin str., 4, +7(921)320-12-62,
nv_bychkova@oparina4.ru, https://orcid.org/0000-0002-6907-2817
Lyubov V. Krechetova, Dr. Med. Sci., Head of the Laboratory of Clinical Immunology of the Institute of Reproductive Medicine, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, 117997, Russia, Moscow, Ac. Oparin str., 4, +7(916)647-39-29,
l_krechetova@oparina4.ru, http://orcid.org/0000-0001-5023-3476
Alla A. Gavisova, Dr. Med. Sci., Head of the 1st Gynecological Departament of the Institute of Reproductive Medicine, Academician V.I. Kulakov National Medical Research Center for Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, 117997, Russia, Moscow, Ac. Oparin str., 4, a_gavisova@oparina4.ru,
https://orcid.org/0000-0003-4700-2786

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